The Impulse Multiprocessing
IAT Manufacturing/Alternate Approach
Announced: November 1998
During November 1998 IAT Manufacturing and Alternate Approach
announced the development of a range of Amigas that would use the
Coldfire processor. Although it is still quite early in development
it already showing promise as a way of continuing the Classic Amiga
line into the next century and could form the basis of range of
cheap Amiga-compatible systems. This is not the first time the
Amiga has been linked with the Coldfire line; during 1995/96 it was
one of the choices for the Amiga Walker project.
The Coldfire series was created by Motorola as a low-cost RISC
descendant of the 68k platform. It reduces the cost of the chip by
switching to an RISC design and stripping the 68k of only the most
essential instructions, this makes it roughly 40% opcode compatible
with 68k processors resulting in many applications not being able
to run. This could be solved in a similar way that support was
added to the 68060 processor by creating a set of libraries that
handle the missing instructions through software rather than
hardware. This would result in many applications running much
slower as the opcodes would have to be emulated in software and a
greater load would be put on the processor. However, considering
the speed increase of the Coldfire (up to 600MIPS) it will not
matter and in some circumstances would allow the application to run
even faster. The only problem would be with games and a few old
applications that access the hardware directly.
IAT Manufacturing (hardware) and Alternate Approach (software)
are currently developing the Impulse Multiprocessing system in a
joint venture. To take advantage of the multi-processing
capabilities a custom Micro-OS is being developed to integrate it
into the AmigaOS, which is not able to do it as standard. Unlike
current approaches to adding a PowerPC to the Amiga the Coldfire
will be autonomous utilising the MCF5307 processor and using
multiple buses (called IMultibus technology). The system will be
entirely modular allowing the production of a wide range of
Amiga-based devices that can be upgraded only when necessary.
The first phase will result in the release of Coldfire systems
working in conjunction with the 68k processor sometime during early
1999. This will involve the sale of complete systems and upgrades
for current A1200 and A4000's through the release of Coldfire
accelerator boards. If these units are successful they will move
onto phase 2 that will use Coldfire processors capable of 600MIPS
and removing the need for 68k altogether.
In a press release IAT manufacturing stated that the planned
system would consist of:
They hope that third party developers will take advantage of the
IBus to produce a range of peripherals and add-ons.
- Two MCF5307 processors (70 MIPS each) + 1 68k processor.
- Two Fully functional FPU's (Floating Point Units).
- 8 Megabit SRAM (12ns access time).
- Three RS232 serial ports.
- M-bus Support (I2C compatible)
- Custom "IBus Expansion with access to programmable chip selects
& DMA controller.
- DRAM controllers
Read the preliminary press
Last Update: 1/11/2001